Well, actually this could be done. The questions to ask: is this the real priority of Zwift now; what are the real long term strategy of Zwift, are they including e-sport only plans or virtual-social development aspect also?
And I’m totally for such a system where there is only one social place for the whole Zwift community. (this doesn’t mean, that clubs, communities, people could not use FB or any other social system outside Zwift…, this is just a choice)
Here is an example of such a plan to develop a whole One Social Eco-system for Zwift:
p.s. and such a system is not “forcing” someone to leave FB or other social network, it is just creating an opportunity and naturally people will stay with it if the whole social experience is satisfied within one system (PM to your friends inside Zwift, social groups and space inside for clubs and communities end so on, so naturally no need to go elsewhere when all the needs are satisfied in one place)